1 // SPDX-License-Identifier: GPL-2.0
8  * Ohad Ben-Cohen <ohad@wizery.com>
16 #include <linux/rpmsg.h>
24 	.name = "rpmsg",
29  * rpmsg_create_channel() - create a new rpmsg channel
31  * @rpdev: rpmsg device
34  * Return: a pointer to the new rpmsg device on success, or NULL on error.
41 	if (!rpdev->ops || !rpdev->ops->create_channel) {  in rpmsg_create_channel()
42 		dev_err(&rpdev->dev, "no create_channel ops found\n");  in rpmsg_create_channel()
46 	return rpdev->ops->create_channel(rpdev, chinfo);  in rpmsg_create_channel()
51  * rpmsg_release_channel() - release a rpmsg channel
53  * @rpdev: rpmsg device
62 		return -EINVAL;  in rpmsg_release_channel()
63 	if (!rpdev->ops || !rpdev->ops->release_channel) {  in rpmsg_release_channel()
64 		dev_err(&rpdev->dev, "no release_channel ops found\n");  in rpmsg_release_channel()
65 		return -ENXIO;  in rpmsg_release_channel()
68 	return rpdev->ops->release_channel(rpdev, chinfo);  in rpmsg_release_channel()
73  * rpmsg_create_ept() - create a new rpmsg_endpoint
74  * @rpdev: rpmsg channel device
77  * @chinfo: channel_info with the local rpmsg address to bind with @cb
79  * Every rpmsg address in the system is bound to an rx callback (so when
80  * inbound messages arrive, they are dispatched by the rpmsg bus using the
84  * bind a callback, and possibly some private data too, to an rpmsg address
85  * (either one that is known in advance, or one that will be dynamically
88  * Simple rpmsg drivers need not call rpmsg_create_ept, because an endpoint
89  * is already created for them when they are probed by the rpmsg bus
90  * (using the rx callback provided when they registered to the rpmsg bus).
93  * endpoint, their rx callback is bound to their rpmsg address, and when
95  * equals to the src address of their rpmsg channel), the driver's handler
99  * additional rpmsg addresses, and bind them to different rx callbacks.
107  * dynamically assign them an available rpmsg address (drivers should have
119 	return rpdev->ops->create_ept(rpdev, cb, priv, chinfo);  in rpmsg_create_ept()
124  * rpmsg_destroy_ept() - destroy an existing rpmsg endpoint
127  * Should be used by drivers to destroy an rpmsg endpoint previously
133 	if (ept && ept->ops)  in rpmsg_destroy_ept()
134 		ept->ops->destroy_ept(ept);  in rpmsg_destroy_ept()
139  * rpmsg_send() - send a message across to the remote processor
140  * @ept: the rpmsg endpoint
146  * endpoint belongs to, using @ept's address and its associated rpmsg
148  * In case there are no TX buffers available, the function will block until
150  * happens, -ERESTARTSYS is returned.
159 		return -EINVAL;  in rpmsg_send()
160 	if (!ept->ops->send)  in rpmsg_send()
161 		return -ENXIO;  in rpmsg_send()
163 	return ept->ops->send(ept, data, len);  in rpmsg_send()
168  * rpmsg_sendto() - send a message across to the remote processor, specify dst
169  * @ept: the rpmsg endpoint
177  * In case there are no TX buffers available, the function will block until
179  * happens, -ERESTARTSYS is returned.
188 		return -EINVAL;  in rpmsg_sendto()
189 	if (!ept->ops->sendto)  in rpmsg_sendto()
190 		return -ENXIO;  in rpmsg_sendto()
192 	return ept->ops->sendto(ept, data, len, dst);  in rpmsg_sendto()
197  * rpmsg_send_offchannel() - send a message using explicit src/dst addresses
198  * @ept: the rpmsg endpoint
208  * In case there are no TX buffers available, the function will block until
210  * happens, -ERESTARTSYS is returned.
220 		return -EINVAL;  in rpmsg_send_offchannel()
221 	if (!ept->ops->send_offchannel)  in rpmsg_send_offchannel()
222 		return -ENXIO;  in rpmsg_send_offchannel()
224 	return ept->ops->send_offchannel(ept, src, dst, data, len);  in rpmsg_send_offchannel()
229  * rpmsg_trysend() - send a message across to the remote processor
230  * @ept: the rpmsg endpoint
238  * In case there are no TX buffers available, the function will immediately
239  * return -ENOMEM without waiting until one becomes available.
248 		return -EINVAL;  in rpmsg_trysend()
249 	if (!ept->ops->trysend)  in rpmsg_trysend()
250 		return -ENXIO;  in rpmsg_trysend()
252 	return ept->ops->trysend(ept, data, len);  in rpmsg_trysend()
257  * rpmsg_trysendto() - send a message across to the remote processor, specify dst
258  * @ept: the rpmsg endpoint
266  * In case there are no TX buffers available, the function will immediately
267  * return -ENOMEM without waiting until one becomes available.
276 		return -EINVAL;  in rpmsg_trysendto()
277 	if (!ept->ops->trysendto)  in rpmsg_trysendto()
278 		return -ENXIO;  in rpmsg_trysendto()
280 	return ept->ops->trysendto(ept, data, len, dst);  in rpmsg_trysendto()
285  * rpmsg_poll() - poll the endpoint's send buffers
286  * @ept:	the rpmsg endpoint
297 	if (!ept->ops->poll)  in rpmsg_poll()
300 	return ept->ops->poll(ept, filp, wait);  in rpmsg_poll()
305  * rpmsg_trysend_offchannel() - send a message using explicit src/dst addresses
306  * @ept: the rpmsg endpoint
316  * In case there are no TX buffers available, the function will immediately
317  * return -ENOMEM without waiting until one becomes available.
327 		return -EINVAL;  in rpmsg_trysend_offchannel()
328 	if (!ept->ops->trysend_offchannel)  in rpmsg_trysend_offchannel()
329 		return -ENXIO;  in rpmsg_trysend_offchannel()
331 	return ept->ops->trysend_offchannel(ept, src, dst, data, len);  in rpmsg_trysend_offchannel()
336  * rpmsg_set_flow_control() - request remote to pause/resume transmission
337  * @ept:	the rpmsg endpoint
346 		return -EINVAL;  in rpmsg_set_flow_control()
347 	if (!ept->ops->set_flow_control)  in rpmsg_set_flow_control()
348 		return -EOPNOTSUPP;  in rpmsg_set_flow_control()
350 	return ept->ops->set_flow_control(ept, pause, dst);  in rpmsg_set_flow_control()
355  * rpmsg_get_mtu() - get maximum transmission buffer size for sending message.
356  * @ept: the rpmsg endpoint
367 		return -EINVAL;  in rpmsg_get_mtu()
368 	if (!ept->ops->get_mtu)  in rpmsg_get_mtu()
369 		return -ENOTSUPP;  in rpmsg_get_mtu()
371 	return ept->ops->get_mtu(ept);  in rpmsg_get_mtu()
376  * match a rpmsg channel with a channel info struct.
377  * this is used to make sure we're not creating rpmsg devices for channels
385 	if (chinfo->src != RPMSG_ADDR_ANY && chinfo->src != rpdev->src)  in rpmsg_device_match()
388 	if (chinfo->dst != RPMSG_ADDR_ANY && chinfo->dst != rpdev->dst)  in rpmsg_device_match()
391 	if (strncmp(chinfo->name, rpdev->id.name, RPMSG_NAME_SIZE))  in rpmsg_device_match()
414 	return sprintf(buf, format_string, rpdev->path);		\
429 		return -ENOMEM;						\
433 	old = rpdev->member;						\
435 		rpdev->member = new;					\
438 		rpdev->member = NULL;					\
452 	return sprintf(buf, "%s\n", rpdev->member);			\
456 /* for more info, see Documentation/ABI/testing/sysfs-bus-rpmsg */
470 	if (len != -ENODEV)  in modalias_show()
473 	return sprintf(buf, RPMSG_DEVICE_MODALIAS_FMT "\n", rpdev->id.name);  in modalias_show()
488 /* rpmsg devices and drivers are matched using the service name */
492 	return strncmp(id->name, rpdev->id.name, RPMSG_NAME_SIZE) == 0;  in rpmsg_id_match()
495 /* match rpmsg channel and rpmsg driver */
500 	const struct rpmsg_device_id *ids = rpdrv->id_table;  in rpmsg_dev_match()
503 	if (rpdev->driver_override)  in rpmsg_dev_match()
504 		return !strcmp(rpdev->driver_override, drv->name);  in rpmsg_dev_match()
509 				rpdev->id.driver_data = ids[i].driver_data;  in rpmsg_dev_match()
522 	if (ret != -ENODEV)  in rpmsg_uevent()
526 					rpdev->id.name);  in rpmsg_uevent()
530  * when an rpmsg driver is probed with a channel, we seamlessly create
531  * it an endpoint, binding its rx callback to a unique local rpmsg
535  * processor (needed in case the driver is exposing an rpmsg service).
540 	struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);  in rpmsg_dev_probe()
549 	if (rpdrv->callback) {  in rpmsg_dev_probe()
550 		strscpy(chinfo.name, rpdev->id.name, sizeof(chinfo.name));  in rpmsg_dev_probe()
551 		chinfo.src = rpdev->src;  in rpmsg_dev_probe()
554 		ept = rpmsg_create_ept(rpdev, rpdrv->callback, NULL, chinfo);  in rpmsg_dev_probe()
557 			err = -ENOMEM;  in rpmsg_dev_probe()
561 		rpdev->ept = ept;  in rpmsg_dev_probe()
562 		rpdev->src = ept->addr;  in rpmsg_dev_probe()
564 		ept->flow_cb = rpdrv->flowcontrol;  in rpmsg_dev_probe()
567 	err = rpdrv->probe(rpdev);  in rpmsg_dev_probe()
573 	if (ept && rpdev->ops->announce_create) {  in rpmsg_dev_probe()
574 		err = rpdev->ops->announce_create(rpdev);  in rpmsg_dev_probe()
584 	if (rpdrv->remove)  in rpmsg_dev_probe()
585 		rpdrv->remove(rpdev);  in rpmsg_dev_probe()
596 	struct rpmsg_driver *rpdrv = to_rpmsg_driver(rpdev->dev.driver);  in rpmsg_dev_remove()
598 	if (rpdev->ops->announce_destroy)  in rpmsg_dev_remove()
599 		rpdev->ops->announce_destroy(rpdev);  in rpmsg_dev_remove()
601 	if (rpdrv->remove)  in rpmsg_dev_remove()
602 		rpdrv->remove(rpdev);  in rpmsg_dev_remove()
606 	if (rpdev->ept)  in rpmsg_dev_remove()
607 		rpmsg_destroy_ept(rpdev->ept);  in rpmsg_dev_remove()
611 	.name		= "rpmsg",
620  * A helper for registering rpmsg device with driver override and name.
626 	struct device *dev = &rpdev->dev;  in rpmsg_register_device_override()
630 		strscpy_pad(rpdev->id.name, driver_override, RPMSG_NAME_SIZE);  in rpmsg_register_device_override()
632 	dev_set_name(dev, "%s.%s.%d.%d", dev_name(dev->parent),  in rpmsg_register_device_override()
633 		     rpdev->id.name, rpdev->src, rpdev->dst);  in rpmsg_register_device_override()
635 	dev->bus = &rpmsg_bus;  in rpmsg_register_device_override()
639 		ret = driver_set_override(dev, &rpdev->driver_override,  in rpmsg_register_device_override()
652 		kfree(rpdev->driver_override);  in rpmsg_register_device_override()
653 		rpdev->driver_override = NULL;  in rpmsg_register_device_override()
678 		return -EINVAL;  in rpmsg_unregister_device()
689  * __register_rpmsg_driver() - register an rpmsg driver with the rpmsg bus
697 	rpdrv->drv.bus = &rpmsg_bus;  in __register_rpmsg_driver()
698 	rpdrv->drv.owner = owner;  in __register_rpmsg_driver()
699 	return driver_register(&rpdrv->drv);  in __register_rpmsg_driver()
704  * unregister_rpmsg_driver() - unregister an rpmsg driver from the rpmsg bus
711 	driver_unregister(&rpdrv->drv);  in unregister_rpmsg_driver()
722 		pr_err("failed to register rpmsg class\n");  in rpmsg_init()
728 		pr_err("failed to register rpmsg bus: %d\n", ret);  in rpmsg_init()